Re: [Boost-users] Bad performance over UDP and ASIO

Subject: Re: [Boost-users] Bad performance over UDP and ASIO
From: Cliff Green (cliffg_at_[hidden])
Date: 2008-12-19 12:54:31

Try the following to see if the (probably small) reduction in memory allocation / deallocation helps (I really doubt it will help much - I think there's something else that is causing problems, since you're seeing some major performance problems that probably have nothing to do with the code sample you posted):

Change:

IProtocolPacket* packet = iter->Next();
std::vector<asio::const_buffer> buffs(2); 
buffs.push_back(asio::const_buffer(packet->GetHeader(), packet->GetHeaderSize());
buffs.push_back(asio::const_buffer(packet->GetBody(), packet->GetBodySize());

To:

IProtocolPacket* packet = iter->Next();
boost::array<asio::const_buffer, 2> buffs = { 
  asio::buffer(packet->GetHeader(), packet->GetHeaderSize()),
  asio::buffer(packet->GetBody(), packet->GetBodySize())
};

(Warning - uncompiled and untested.)
---
Hmmm - I see something that could be suspicious: "packet" is a local variable (short lifetime) - are the pointers obtained from packet valid (point to good memory) until the handle_send function is called? Asio does not own the data that the buffer objects wrap.
Otherwise, you might want to post your io_service run code to see if there's something suspicious there.
Cliff